Over the years, a variety of compositions have been developed to treat chronic skin problems such as acne, sun damage, precancerous lesions, scars, pigmentation disorders, wrinkles and the like. These either supplement or prevent the loss of nutrients needed for healthy skin or remove regions of damaged skin. Included in the former category are skin creams, lotions and ointments that are generally available over-the-counter. These creams either act to prevent water loss from the skin or to deliver nutrients into the dermal layers. Suitable examples of such creams can be found in U.S. Pat. Nos. 4,424,234 and 4,235,889. Also, prescription medical creams and antibiotics used to treat acne vulgaris or other skin conditions are known to those skilled in the art.
For the most part, only three methods are now in routine medical use for removing damaged skin. They all involve the application of particular chemicals. The first can be termed the trichloroacetic acid peel; the second, the resorcinol or salicylic acid peel; and third, the chemical peel. All three are of only limited use.
The trichloroacetic acid peel involves the application of trichloroacetic acid to the damaged area, followed by a short reaction time to allow it to interact with the damaged skin. Several days later, the damaged area peels off. The limitation of this method in that it is generally not effective for dark skinned people with significant pigmentation because it peels the skin unevenly, and thus leaves unevenly pigmented skin. For that reason, only fair skinned people are peeled with trichloroacetic acid treatment. Blacks and other dark skin groups are excluded.
The second peal process involves the use of either resorcinol or salicylic acid. The use of either of these chemicals is generally restricted to correcting superficial skin problems. They are further limited in that they often can cause skin irritation.
The third peel process, or chemical peel, also has numerous drawbacks. First, it involves the use of phenol, which presents problems of toxicity in some cases. Thus, this method must be carried out in a hospital or in a similar controlled setting. In addition, the method is very painful and often requires that the patient be given medication during its application. Further, while the procedure does peel the skin evenly, it nevertheless often leaves uneven pigmentation of varying skin shades, or total loss of color. Finally, it does not lend itself to repeat applications because of its severe nature.
In addition to the above-described three types of skin peels, there exist a number of less useful materials and procedures. For example, short exposure to ultraviolet light (UVA or UVB wavelengths) is known to be beneficial for psoriasis, vitiligo and mycosis fungoids and simultaneously causes tanning of the skin. None of these methods uses full spectrum sun lamps.
It should be apparent from the above that there is a need for a composition for treating chronic skin disorders, particularly one which would be universally applicable to all races, that is easy to use and, if need be, can be used repeatedly.